Physicochemical Properties of Soils from Grasslands and Forests in Two Protected Areas Across Temperate and Subtropical Zones of Nepal

Abstract

Soil is the largest carbon reservoir, contains soil organic carbon (SOC) influenced by soil properties that is vital for soil fertility and carbon management. This study assessed physicochemical properties in grasslands and forests within the Annapurna Conservation Area (ACA) and Shivapuri Nagarjun National Park (SNNP) across temperate and subtropical zones. The soil temperature was lower and soil moisture was higher in the temperate ACA grassland, compared to sub-tropical SNNP, and in forests compared to the grasslands. Soil electrical conductivity was higher in ACA grasslands than forests, but lower in grassland than forests in SNNP, and overall lower in ACA than in SNNP. Both soil pH and bulk density were higher in grasslands than forests at ACA and SNNP, with a sandy loam soil texture across sites. Soil organic carbon (SOC) and organic matter were higher in ACA than SNNP, with ACA grasslands and SNNP forests showed the highest values. Soil properties differed significantly between grasslands and forests, with soil parameters varying across land uses and climate zones. Most soil characteristics apart SOC being more pronounced in temperate zone than in subtropical one. Hence, grassland and forest soils are key carbon sinks, and these soils require proper management, assessment and conservation